function MenuController( rootElement ) {
	
	this.rootElement = rootElement;
	
	function checkRootElement() {
		var rootNodeName = jQuery(rootElement).get(0).tagName;
		if(rootNodeName != "DIV") {
			throw "Type of main menu root element should be div";
		}
	}
	
	function setCssForTopbarItems( topList ) {
		topList.children("li").each( function() {
			topItem = jQuery(this);
			topItem.addClass("topbar-menu-item");
			topItem.children(":not(ul)").each( function() {
				jQuery(this).addClass("topbar-menu-item");
			});
		});
	}
	
	function setCssForSubItems( topList ) {
		topList.find(":not(.topbar-menu-item)").each( function() {
			var subItem = jQuery(this);
			var subItemTagName = subItem.get(0).tagName;
			if( subItemTagName == "UL" || subItemTagName == "LI" || subItemTagName == "A" ){
				jQuery(this).addClass("sub-menu-item");
			}
		});
	}
	
	function setCssClasses() {
		rootElement.addClass("topbar-menu-item");
		var topList = rootElement.find("ul:first");
		topList.addClass("topbar-menu-item");
		setCssForTopbarItems(topList);
		setCssForSubItems(topList);
	}
	
	function hideAllSubMenus() {
		rootElement.find("ul.sub-menu-item").each( function() {
			jQuery(this).css({
				"display": "none"
			});
		});
	}
	
	function updateStyle(element, style) {
		for(var entry in style) {
			element.css( entry, style[entry] );
		}
	}
	
	function setMouseEventHandlers() {
		rootElement.find("li.topbar-menu-item, li.sub-menu-item").hover( function() {
			var parent = jQuery(this);
			if(parent.hasClass("topbar-menu-item")) {
				updateStyle( parent.find("a:first"), topbarItemSelectedStyle );
			}
			if(parent.hasClass("sub-menu-item")) {
				updateStyle( parent.find("a:first"), subItemSelectedStyle );
			}
			jQuery(this).find("ul:first").each( function() {
				if(parent.hasClass("sub-menu-item")) {
					jQuery(this).css("left", parent.width()+1);
					jQuery(this).css("top", 0);
				}
				jQuery(this).css({visibility: "visible",display: "none"}).show(); 
			});
		}, function() {
			var parent = jQuery(this);
			if(parent.hasClass("topbar-menu-item")) {
				updateStyle( parent.find("a:first"), topbarItemStyle );
			}
			if(parent.hasClass("sub-menu-item")) {
				updateStyle( parent.find("a:first"), subItemStyle );
			}
			parent.find("ul:first").css({
				"visibility": "hidden"
			});
		});
	}
	
	function refresh() {
		var maxHeight = 0;
		rootElement.find("li.topbar-menu-item").each( function() {
			if(jQuery(this).height() > maxHeight) {
				maxHeight = jQuery(this).height();
			}
		});
		if(maxHeight == 0) {
			maxHeight = 37;
		}
		rootElement.height(maxHeight);
	}
	
	function addArrow( arrow, selector ) {
		if( arrow == "") {
			return;
		}
		rootElement.find(selector).each( function() {
			var topbarItem = jQuery(this);
			if(topbarItem.find("li").size() > 0) {
				topbarItem.children("a").each( function() {
					jQuery(this).find("img.menu-arrow").remove();
					jQuery(this).append("<img src=\"" + arrow + "\" class=\"menu-arrow\"/>");
				});
			}
		});
	}
	
	function addArrows() {
		addArrow( topbarArrow, "li.topbar-menu-item" );
		addArrow( submenuArrow, "li.sub-menu-item" );
	}
	
	this.init = function() {
		checkRootElement();
		setCssClasses();
		hideAllSubMenus();
		setMouseEventHandlers();
		addArrows();
		refresh();
	};
	
	this.setRootStyle = function(style) {
		rootElement.css(style);
		refresh();
	};
	
	this.setStyle = function(selector, style) {
		rootElement.find(selector).each( function() {
			jQuery(this).css(style);
		});
		refresh();
	};
	
	var topbarItemStyle = "";
	this.setTopbarItemStyle = function(style) {
		topbarItemStyle = style;
	};
	
	var topbarItemSelectedStyle = "";
	this.setTopbarItemSelectedStyle = function(style) {
		topbarItemSelectedStyle = style;
	};
	
	var subItemStyle = "";
	this.setSubItemStyle = function(style) {
		subItemStyle = style;
	};
	
	var subItemSelectedStyle = "";
	this.setSubItemSelectedStyle = function(style) {
		subItemSelectedStyle = style;
	};
	
	var topbarArrow = "";
	var submenuArrow = "";
	this.setArrows = function(topbar, submenu) {
		topbarArrow = topbar;
		submenuArrow = submenu;
		addArrows();
	};
}

var controller;

jQuery.fn.initMenu = function() {
	controller = new MenuController(jQuery(this));
	controller.init();
};

jQuery.fn.setTopbarStyle = function(style) {
	controller.setRootStyle(style);
};

jQuery.fn.setTopbarItemStyle = function(style) {
	controller.setStyle("a.topbar-menu-item", style);
	controller.setTopbarItemStyle(style);
};

jQuery.fn.setTopbarItemSelectedStyle = function(style) {
	controller.setTopbarItemSelectedStyle(style);
};

jQuery.fn.setSubMenuStyle = function(style) {
	controller.setStyle("ul.sub-menu-item hover", style);
};

jQuery.fn.setSubItemStyle = function(style) {
	controller.setStyle("a.sub-menu-item", style);
	controller.setSubItemStyle(style);
};

jQuery.fn.setSubItemSelectedStyle = function(style) {
	controller.setSubItemSelectedStyle(style);
};

jQuery.fn.setArrows = function(topbar, submenu) {
	controller.setArrows(topbar, submenu);
};